Immunogenetics chapter 22 select topics pp

Topic Outline Overview of the Immune System 1 st and 2 nd lines of Defense The Immune System  B cells  The antibody & antibody diversity  Vaccinations  Breast Feeding  Diagnostic applications  T cells  Allergies

Immune System and Lymphoid Tissue

Let’s take a look at the different types of Leukocytes

Monocyte Neutrophil Eosinophil Basophil Dendritic Cell Lymphocyte

Epidermis Mucosal lining of GI Ciliated epithelium of respiratory tract EXAMPLES FIRST LINE OF DEFENSE Can by physical and chemical

Second line of defense include the following processes:  Phagocytosis  Complement  Interferons  Inflammation  Pyrogens

Phagocytosis

Complement Cascade

3 rd line of defense “The Immune System”

Summary Lines of Defense INNATE ACQUIRED

Immune System B cells T cells

Lymph nodes are contain high concentrations lymphocytes

Let’s look more closely at the B lymphocytes

B Cell: humoral or antibody mediated immunity ANTIBODIES=IMMUNOGLOBULINS Humoral Immunity  Matures in bone marrow  Moves to lymph nodes (& other locations)  Secretes antibodies “as plasma cell”  Also creates “memory” B cells B-lymphocyte

CLONAL SELECTION

Different classes of immunoglobulins or antibodies IgM IgG IgA IgD IgE

Antibody Diversity How do we acquire so many different types of antibodies?  Somatic recombination  Junctional diversity  hypermutations

Antibody genes are composed of segments V J C

Somatic Recombination unology/Flash/somaticrecomb.html unology/Flash/somaticrecomb.html

How are vaccinations related to immunity? Active and Passive

Active Vaccinations: Antibody Production Memory Cells!

The next part gets tricky Onto T Cells

All T cells require cell to cell contact

CD8+ CD4+

T Cells VJC (D) These are some of the General characteristics of the T Cell receptor for antigen recognition. + D in the beta chain

Cytotoxic T Cell and MHC I Antigen presentation CD8+ cell

Cytotoxic T cell= CD8+

Tissue Transplantation MHC proteins differ between individuals

The major histocompatibility complex is a large group of genes on chromosome 6

Helper T Cell and MHC II Antigen presentation

B lymphocytes source of antibodies Overview of T lymphocytes

Cancer cell being attacked by cytotoxic T cells After release of perforin

Allergic Response I.

Allergies B cell also directly stimulated IgE